So is it now acceptable to use the Eaton coil style clutch as "correct". I know John Z said that both were used and I'v seen an original 67 L78 with the Eaton??? I have the Eaton on a 68 L78 with the correct 4 rivet fan.

The Eaton and Schwitzer clutches were used interchangeably on the line - that's what the "opt." (optional) part numbers are in the A.I.M.; different appearance, but same Engineering specs. What makes them hard to find (and expensive) is the unusual combination of the small (1-3/4") bolt circle where the clutch attaches to the water pump hub with the large (3-1/4") bolt circle where the fan attaches to the clutch. Most clutches that use the small bolt circle at the water pump also used the small (3") bolt circle for the fan.